Film illuminators



July 24, 1956 M. LUBOW FILM ILLUMINATORS Filed Jan. 4, 1952 FIG.2

. I I l L l M INVENFR ATTORNEY FILM ILLUMINATORS Morris Lubow, Brooklyn, N. Y., assignor to Wolf X-Ray Products, Inc., New York, N. Y.

Application January 4, 1952, Serial No. 264,972

3 (Ilaims. (Cl. 40-130) This invention relates to film illuminators and more particularly to sheet gripping means associated with such devices.

Film illuminators known in the art are provided with means for gripping the upper edge of sheet film which is being illuminated, such means consisting of individual, spring pressed clips spaced along the top of the device above the glass viewing panel. Such film gripping means have disadvantages common to springs as well as other disadvantages recognized in the art.

Accordingly, an object of this invention is to provide in a device of the character described, improved sheet gripping means which eliminates springs and other resilient means and is based on the use of a plurality of members of high unit weight which are arranged in a manner such that gravity permits them to exert a gripping force on marginal portions of the sheet.

A further object of this invention is to provide in a device of the character described, improved film gripping means wherein a plurality of heavy members having curved surfaces are arranged in aligned relation to a rigid surface whereby such members tend to move downwardly due to the action of gravity and to press against the rigid surface at tangential points of contact therewith.

Another object of this invention is to provide in a device of the character described, improved film gripping means located above the top edge of the glass viewing panel thereof and arranged to grip the top margin of a sheet of film against a fixed, rigid surface immediately above and independent of the glass panel, thereby permitting the glass panel to be removed from the device for shipment or replacement, without alfecting the gripping means.

Still another object of this invention is to provide improved sheet gripping means including a plurality of heavy spheres arranged in means permitting the spheres to move downwardly under the force of gravity while contacting a rigid surface whereby to exert a pressing or gripping action with respect to the rigid surface at a plurality of points spaced at a distance no greater than the diameters of such spheres.

Still a further object of this invention is to provide in a device of the character described, improved sheet gripping means located in an upper portion thereof and arranged to provide a smooth frame for the glass panel which is free of projections or bulges.

Yet another object of this invention is to provide sheet gripping means which is readily and economically fabricated, easily integrated with a film illuminator or the like, and which is rugged and eificient in use.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

in the accompanying drawing:

Fig. l is a front elevational view of a film illuminator embodying the invention;

Fig. 2 is a side elevational view thereof;

Patented July 24, 1956 Fig. 3 is a vertical sectional view, enlarged, taken on the line 3-3 in Fig. 1;

Fig. 4 is a vertical section, enlarged, similar to Fig. 3 and showing a modification thereof; and

Fig. 5 is a partial elevational view with parts cut away, of the upper frame portion, showing a modified form of gripping member.

Referring in detail to the drawing and particularly to Fig. 1, 1i} designates a film illuminator embodying the invention. The same comprises a rectangular shaped, hollow casing 11, having a back wall 12, side walls 13, a top wall 14 and a bottom wall 15. Illuminating means 16, which may take the form of fluorescent tubes or incandescent bulbs, is suitably positioned within the easing and provided with suitable reflector means, in a manner known in the art. Wiring 12a from the illuminating means may be brought out through back wall 12 and arranged for plugging into an electrical outlet.

The front of casing 11 includes an overlapping rectangular frame 17 which includes side portions 18, a bottom portion 19 and a top portion 29. The frame 17 is adapted to removably receive therein a light transmitting panel 21 which may be of glass or of other suitable material.

The frame 17 is hollow, being made of suitably bent metal and is welded or otherwise secured to the casing walls. The top portion of frame 17 includes a top wall 22, a downwardly extending, vertical front wall 23 and a downwardly and inwardly extending wall portion 24 which terminates in an outwardly turned lip 25. Located within the frame top portion 2a is a longitudinally extending, angularly bent metal member which includes at its lower end a pair of right angle portions 26, 27, a second pair of right angle portions 28, 29 at its upper end and a vertical flange 36 which is welded or otherwise secured to the inner face of wall 23, thereby positioning the bent member within the frame portion.

The angle portions 26, 27 are adapted to receive the glass panel 21, while the angle portions 28, 29 located forwardly of the portions 26, 27, together with walls 23, 2d, define a longitudinally extending hollow space 31 and a longitudinally extending slot or opening 32 at lip 25. As shown in Fig. 3, lip 25 is disposed slightly below angle portion 27 so that slot 32 is located slightly below the top edge of plate 21. Angle portion 28 is parallel to plate 2.1 and slightly forward of the front face thereof.

Located within hollow space 31 are a plurality of similar, short cylindrical members 33 formed of a material of high unit weight, such as steel or the like. Such members have a diameter less than the transverse dimension of space 31 and are freely movable therein in a radial direction. Preferably, the members 33 are of a length and number as to fill the longitudinal space in end to end relation. it will be apparent from a consideration of Fig. 3, that each of the members 33 is supported by opposed portions of walls 24, 28 and makes tangential contact therewith. The point of contact on wall 28 is immediately above the top edge of panel 21.

When using the illuminator id, a sheet of film F which is to be illuminated and viewed, is positioned vertically in contact with panel 21 and moved upwardly as indicated by the arrow in full lines until the top edge of the film passes through slot 32 and between the members 33 and wall 28, the members 33 moving readily to admit the film edge. When the film edge passes the tangential point of contact as between members 33 and wall 28, the film will be gripped therebetween by virtue of the weight of members 33 which tend to move downwardly and towards wall 23 due to the inclination of wall 24. The film F is readily removed from the device by merely pulling on the same in a downward direction as indicated 3 by the arrow in broken lines, the members 33 being free to allow the release of the film.

It is apparent that with the gripping means as shown, film F is gripped between surfaces which are integral with the device, thus allowing the panel 21 to be readily removed and replaced without interfering with the gripping means. In the event that panel 21 is broken, the members 33 will not roll out into the interior of casing 11 and cause possible injury to the illuminating means 16. Furthermore, the panel 21 may be separately packaged and shipped apart from the casing and readily inserted in the frame of the casing by the user of the device.

While the frame portion 20 projects forwardly somewhat, of the panel 21, the film gripping means may be so arranged and located as to provide a frame portion 200 which is almost flush with panel 21, as shown in Fig. 4. Here, the frame portion 20a includes a top wall 22a and a vertical, downwardly extending front wall 34 which terminates at its lower edge in an outwardly turned lip 35. Located interiorly of frame portion 20a is a longitudinally extending, angularly bent member which includes a pair of right angle portions 26a, 27a at its lower end, an inclined wall 36 extending upwardly and inwardly of the front edge of angle portion 27a, a second inclined wall 37 extending upwardly and outwardly from the upper edge of wall 36, and finally, a vertical flange 38 which is welded or otherwise secured to the inner face of wall 34, thus positioning the angularly bent member within the frame portion 20a.

The angle portions 260, 27a are adapted to receive the top edge of panel 21. The walls 36, 37, together with wall 34 define a longitudinal space of triangular cross section, the apex of which is located rearwardly of front wall 34. The angular junction of walls 36 and 27a is spaced slightly inwardly of the back face of wall 34 and slightly above lip 35, thus providing a longitudinally extending slot or opening 32a. The members 33 are disposed in the triangular space and are supported by opposed portions of walls 34, 36, making tangential contact therewith. When film F is moved upwardly on panel 21, the top edge passes through slot 32a and is pressed against the back face of wall 34 by the members 33. The back face of wall 34 being parallel to panel 21 and only slightly spaced from the front face thereof, film F will be disposed in substantial contact with the panel while gripped at its top edge, independently of the panel. Thus the panel 21 may be removed or replaced without affecting the gripping means, as described above.

While the cylindrical members 33 are quite efiicient as gripping elements, unless such members are precision formed, there may be slight variations in diameter along the axial extent thereof, thereby reducing the net amount of tangential contact relative to walls 28, 34 and producing a less effective gripping action. Accordingly, in lieu of cylindrical members 33, there may be used spherical members 33:: of high unit weight material such as steel, heavy agate, or the like. With the longitudinal space in frame portions 20 or 20a filled with spherical members 33a, tangential contact with wall 28 or 34 is insured at relative close intervals along the extent thereof, thus providing efiicient gripping action on film F, see Fig. 5.

The frame portion 20 and 20a may be provided with an opening 39 at one end thereof for introducing or removing members 33, 33a, a pivoted cover 40 being provided for the opening.

It will thus be seen that there is provided a device of the character described, in which the several objects of this invention are achieved and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above described invention, and as various changes might be made in the embodiments set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing, is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to protect by Letters Patent:

1. In a film illuminator having a casing including a front frame portion, a glass panel removably mounted in said frame portion, said frame comprising an angle portion for receiving said panel, the upper end of said frame including a wall having a surface substantially coplanar with the front face of said panel, a second wall in spaced, fixed relation to said first wall and including a wall portion inclined downwardly relative to said first wall to provide a longitudinal slot at the lower edge thereof aligned with the outer face of said panel, a third wall interconnecting upper portions of said first and second walls and a plurality of members of substantial unit weight enclosed by said first, second and third walls and having curved surfaces freely positioned on opposed portions of said first and second walls with the curved surfaces in tangential contact with said walls for gripping a sheet of film disposed with its inner surface in contact throughout the extent thereof with the front face of said panel when the upper edge of said film is inserted in said slot and moved upwardly for engagement by said first wall and said members, said members having a transverse dimension greater than the transverse dimension of said slot and illuminating means in said casing located rearwardly of said panel for illuminating the gripped sheet of film.

2. A film illuminator as in claim 1 wherein said first wall is an outer wall and said second wall is disposed inwardly of said first wall.

3. A film illuminator as in claim 1 wherein said second wall is an outer wall and said first wall is disposed inwardly of said second wall.

References Cited in the file of this patent UNITED STATES PATENTS 1,455,474 Brown May 15, 1923 1,602,341 Day Oct. 15, 1926 1,739,057 Bock Dec. 10, 1929 2,516,270 Swain July 25, 1950 2,530,821 Hubbel Nov. 21, 1950 2,534,637 Sussin Dec. 19, 1950 FOREIGN PATENTS 164,145 Switzerland Dec. 1, 1933 342,601 Italy Aug. 11, 1936 581,088 Great Britain Oct. 1, 1946 

